A year after being relegated, Worcester returned to the Premiership taking the second leg of their play-off with the Cornish Pirates in much the way they did the first. They took an early lead, extended it around half-time and then hung on for dear life.

"That was horrendous," said their coach Richard Hill. "At 25-6 I was relaxed, but so were some of my players and the Pirates made it very tough in that last half hour. We knew what to expect, but just fell asleep a bit."

However, despite two late tries for the Pirates – the second a penalty try which also reduced Worcester to 14 men for the last seven minutes – the Warriors ended with an aggregate advantage of 14 points, thus ending any chance Leeds had of a reprieve from the drop.

Hill will now spend the summer introducing the crop of new players he has already signed as the Warriors beef up their squad. "We have some good recruits coming," said Hill, "this club has the financial means to recruit good players." First to arrive is likely to be the scrum-half Shaun Perry, who was with Hill at Bristol and was signed from Brive almost three months ago in anticipation of this victory.

As for the Pirates, with a ground that holds only 3,400 they were never going to be allowed to play in the Premiership and, despite their heroics home and away, must now look to losing several of their brighter players with Matt Hopper heading for Harlequins and the full-back Rob Cook and the centre Tom Luke among those talking to other clubs.

They kicked off at Sixways with a nine-point deficit from the first leg in Penzance and seven changes, including a new front row. Worcester settled for one, leaving their pack to pick up where it had left off and within 12 minutes had their reward with a try from the wing Marcel Garvey.

Opting for scrums instead of penalties, the Worcester pack put the squeeze on so well that the Pirates were in full retreat when Garvey stepped in off his wing. The conversion and a Goode drop-goal pushed the aggregate lead out to 19 shortly before half-time, but by then it was clear that Worcester's promotion would not be without alarms – especially when Jonny Bentley got his hands on the ball.

As at Penzance, the fly-half was not overwhelmed by support runners, but he put Worcester on their heals, turning the defence inside out before the captain Chris Pennell halted the run, 10 metres from the tryline.

If that was the first big hint of what was to come, Pirates first had to suffer. Two minutes into the second half Miles Benjamin zipped home from 30 yards and then made the third Worcester try for Andy Goode. Benjamin, top scorer in the championship this season and playing his 100th game for Worcester, was sent clear by the Scotland centre Alex Grove and then set Goode on the same track up the left wing two minutes later.

Goode converted the first and missed adding to his own try, but the gap was up to 28 points. That should have been that, but for some nifty handling by Bentley, who trimmed the aggregate deficit to 21 when he worked the centre Drew Locke away down the left, Cook adding the extras before the last pulsating quarter and the jitters that followed the penalty try.